Film sticking device, film sticking method, and electronic paper manufacturing method

ABSTRACT

Disclosed is a film sticking device that sticks a first film substrate and a second film substrate together on a curved-surface shape. The film sticking device includes a mold having a curved attachment surface formed into a desired curved-surface shape; an attracting and holding unit capable of relatively moving on the curved attachment surface and having plural vacuum chambers on which an attracting surface for attracting and holding the second film substrate is provided; and a suctioning unit capable of separately applying suction processing to the plural vacuum chambers. The suctioning unit starts, as the attracting and holding unit moves, the suction processing of the vacuum chamber corresponding to a position opposing the second film substrate and sequentially stops, as the second film substrate is stuck to the first film substrate, the suction processing of the vacuum chamber corresponding to the stuck second film substrate.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a U.S. continuation application filed under 35U.S.C. 111(a) claiming benefit under 35 U.S.C. 120 and 365(c) of PCTapplication JP2008/064547, filed on Aug. 13, 2008, the entire contentsof which are incorporated herein by reference.

FIELD

The embodiment discussed herein is generally related to film stickingdevices, film sticking methods, and electronic paper manufacturingmethods, and in particular, to a film sticking device that curves andsticks plural film substrates together, a film sticking method, and anelectronic paper manufacturing method.

BACKGROUND

Up until now, there have been discussed methods for manufacturing aplastic laminated body configured to shorten a processing time whileavoiding influences by resin flowing and problems in contractiondistribution at the time of cooling, to have a high freedom degree inconstituent members of a film and a base material, and not to berequired to process a mold for shaping the base material with highprecision.

-   Patent Document 1: Japanese Laid-open Patent Publication No.    2005-161528

SUMMARY

According to an aspect of the present invention, there is provided afilm sticking device that sticks a first film substrate and a secondfilm substrate together on a curved-surface shape, the film stickingdevice including a mold having a curved attachment surface to which thefirst film substrate is attached, the curved attachment surface beingformed into a desired curved-surface shape; an attracting and holdingunit that is configured to be capable of relatively moving on the curvedattachment surface and has plural vacuum chambers on which an attractingsurface for attracting and holding the second film substrate isprovided; and a suctioning unit capable of separately applying suctionprocessing to the plural vacuum chambers; wherein the suctioning unit isconfigured to start, as the attracting and holding unit moves, thesuction processing of the vacuum chamber corresponding to a positionopposing the second film substrate and sequentially stop, as the secondfilm substrate is stuck to the first film substrate, the suctionprocessing of the vacuum chamber corresponding to the stuck second filmsubstrate.

The object and advantages of the present invention will be realized andattained by means of the elements and combinations particularly pointedout in the claims.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and arenot restrictive of the present invention, as claimed.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1A is a schematic configuration diagram of a film sticking deviceas an example of a conventional technique (before film substrates arestuck together);

FIG. 1B is a schematic configuration diagram of the film sticking deviceas the example of the conventional technique (when the film substratesare stuck together);

FIG. 2 is a diagram illustrating the basic configuration of a filmsticking device as an example of the present invention, in which acurved attracting surface is formed into an upwardly projecting shape;

FIG. 3 is a schematic diagram illustrating the enlarged view of theattracting and holding unit of the film sticking device illustrated inFIG. 2;

FIG. 4 is a diagram illustrating the basic configuration of a filmsticking device as an example of the present invention, in which acurved attracting surface is formed into a recessed shape;

FIG. 5 is a configuration diagram of the film sticking device accordingto an embodiment of the present invention;

FIG. 6A is a diagram for illustrating the configuration of an attractingdrum;

FIG. 6B is a diagram illustrating the cross section of the attractingdrum;

FIG. 7 is a block diagram showing the control system of the attractingdrum of the film sticking device according to the embodiment of thepresent invention;

FIG. 8 is a timing chart illustrating the timings of the ON/OFF forsuction processing with respect to the vacuum chambers of the attractingdrum;

FIG. 9 is a flowchart illustrating the operations of the film stickingdevice according to the embodiment of the present invention; and

FIG. 10 is a configuration diagram illustrating another embodiment inwhich the curved attracting surface of a mold is formed into a waveshape.

DESCRIPTION OF EMBODIMENTS

It has been expected that, for example, advertising on trains and POP(point of purchase) advertising on streets be replaced by electronicpapers from the viewpoint of saving paper resources and low powerconsumption. In applying the electronic papers, installation places areassumed to be those having curved surfaces such as upper parts on trainsand poles of buildings. To obtain high durability and secured visibilityrequired for applying the electronic papers, it is desirable that theelectronic papers be shipped after being formed into a desiredcurved-surface shape in a manufacturing step.

Further, in one of electronic paper manufacturing steps, plural filmsubstrates are stuck together. In forming a curved-surface shape in thisstep, however, a present technique (see Patent Document 1) includeslaminating plural resin sheets with each other. Specifically, thelamination of the sheets is performed according to the following method.First, as illustrated in FIG. 1A, two types of molds, i.e., a femalemold 2 formed into a desired curved-surface shape and a male mold 3formed into a shape opposing the female mold 2, are prepared. Then, filmsubstrates 5A and 5B to be stuck together are attracted and held by thefemale mold 2 and the male mold 3. Subsequently, as illustrated in FIG.1B, pressure (as indicated by an arrow F) is applied to the two types ofmolds 2 and 3 in an engaged state. Thus, the film substrates 5A and 5Bare stuck together.

However, the above method causes the following problems (a) through (d).

(a) The two types of dedicated molds 2 and 3 become essential, and thesurfaces (as indicated by numerals 2 a and 3 a in FIG. 1A) of theopposing molds 2 and 3 require high processing accuracy so as to beengaged with each other.

(b) When three or more film substrates are stuck together, a curvatureradius is varied in accordance with an increase in the thickness of thefilm substrates. Therefore, a mold having a different curvature radiusis separately required.

(c) Since the entire surfaces of the film substrates are stuck togetherat once, air bubbles existing in an adhesive or the like are notreleased. To release the air bubbles, an air-bubbles releasing step isseparately required after the substrates are stuck together.

(d) In applying an adhesive for sticking the substrates together,unevenness occurs in the adhesive due to the curved shapes of the molds2 and 3, which results in the thickness of a product being uneven.

In order to solve the above problems, the present invention may have ageneral object of providing an improved useful film sticking device, afilm sticking method, and an electronic paper manufacturing method.

More specifically, the present invention may have an object of providinga film sticking device capable of reliably sticking together plural filmsubstrates formed into a curved surface without causing air bubbles toremain inside the film substrates by the use of a simple manufacturingfacility, a film sticking method, and an electronic paper manufacturingmethod.

Next, referring to the accompanying drawings, a description is made ofan embodiment of the present invention.

FIG. 2 is a diagram illustrating the basic configuration of a filmsticking device 10A as an example of the present invention. FIG. 3 is adiagram illustrating the enlarged view of an attracting and holding unit12 provided in the film sticking device 10A. The film sticking device10A is a device that sticks a film substrate 20A and a film substrate20B together. The film sticking device 10A is composed of a mold 11A,the attracting and holding unit 12, a suctioning unit 17, and the like.

The mold 11A has a curved attracting surface 15A (specifically, aprojecting semi-cylindrical surface) on its side opposing the attractingand holding unit 12. In an example illustrated in FIG. 2, the curvedattracting surface 15 projects upwardly. The curved attracting surface15A has a multiplicity of minute holes formed therein, and the mold 11Ais connected to the suctioning unit 17. As the suctioning unit 17 isdriven, suction processing is applied through the minute holes of thecurved attracting surface 15A. Accordingly, the film substrate 20A isattracted onto the curved attracting surface 15A. Thus, the filmsubstrate 20A is attached to the mold 11A.

As illustrated in an enlarged view in FIG. 5, the attracting and holdingunit 12 has a cylindrical shape as a whole and configured to rotateabout a rotary shaft 40 in a direction as indicated by an arrow A inFIG. 5. As described below, the attracting and holding unit 12 has thefunction of sticking (attaching) the film substrate 20B to the filmsubstrate 20A by relatively moving on the mold 11A while appropriatelyholding or not holding the film substrate 20B.

Further, as to the relative movement of the mold 11A with respect to theattracting and holding unit 12, it may be also arranged that the mold11A is moved with the attracting and holding unit 12 fixed or theattracting and holding unit 12 is moved with the mold 11A fixed. Notethat prior to this stick processing, an adhesive is applied to at leastone of the film substrate 20A and the film substrate 20B.

The attracting and holding unit 12 has internally plural (eight in thisembodiment) vacuum chambers of a first vacuum chamber 13-1 through aneighth vacuum chamber 13-8. The peripheral surfaces of the first vacuumchamber 13-1 through the eighth vacuum chamber 13-8 are, respectively, afirst attracting surface 14-1 through an eighth attracting surface 14-8having a multiplicity of minute holes formed therein.

Further, the suctioning unit 17 is also connected to the attracting andholding unit 12 and configured to be capable of applying the suctionprocessing to the first vacuum chamber 13-1 through the eighth vacuumchamber 13-8. In this case, the suctioning unit 17 is configured to becapable of separately applying the suction processing to each of thefirst vacuum chamber 13-1 through the eighth vacuum chamber 13-8.

Accordingly, as the suctioning unit 17 is driven, the suction processingis applied through the minute holes of the first attracting surface 14-1through the eighth attracting surface 14-8 of the first vacuum chamber13-1 through the eighth attracting surface 13-8. Thus, the filmsubstrate 20B is attached to the attracting and holding unit 12.

At this time, since the suctioning unit 17 is configured to be capableof separately applying the suction processing to each of the firstvacuum chamber 13-1 through the eighth vacuum chamber 13-8, theattracting and holding unit 12 can hold the film substrate 20B over itsprescribed angle range rather than at its entire circumference.

For example, when the suctioning unit 17 applies the suction processingonly to the first vacuum chamber 13-1, the film substrate 20B isattracted and held only by the first attracting surface 14-1. Further,when the suctioning unit 17 applies the suction processing only to thesecond vacuum chamber 13-2 and the third vacuum chamber 13-3, the filmsubstrate 20B is attracted and held only by the second attractingsurface 14-2 and the third attracting surface 14-3.

Next, a description is made of the operations of the film stickingdevice 10A thus configured.

In the example illustrated in FIG. 2, the mold 11A moves in a directionas indicated by an arrow V in FIG. 2 with the attracting and holdingunit 12 fixed. Thus, the attracting and holding unit 12 is configured torelatively moving on the curved attracting surface 15A of the mold 11Ain a direction (a left direction in FIG. 2) opposite to the direction asindicated by the arrow V.

After the film substrate 20A is positioned and placed on the curvedattracting surface 15A, the suctioning unit 17 applies the suctionprocessing to the mold 11A. Consequently, the film substrate 20A is heldon the curved attracting surface 15A by the suctioning force of thesuctioning unit 17.

At the time of starting stick processing for the film substrate 20A andthe film substrate 20B (hereinafter referred to as a sticking starttime), the attracting and holding unit 12 is at a position (hereinafterreferred to as a sticking start position) as indicated by an arrow P1 onthe curved attracting surface 15A in FIG. 2. Further, at the stickingstart time, the attracting and holding unit 12 holds the film substrate20B over a range of 180° of its periphery.

As described above, the attracting and holding unit 12 has the firstvacuum chamber 13-1 through the eighth vacuum chamber 13-8. Along withthe movement of the attracting and holding unit 12, the suctioning unit17 applies the suction processing to the vacuum chamber at a positionwhere the film substrate 20B opposes the front surface of the attractingand holding unit 12. Thus, the film substrate 20B is held by theattracting surface to which the suction processing is applied.

Conversely, as the film substrate 20B is stuck to the film substrate 20Aalong with the movement of the attracting and holding unit 12, thesuctioning unit 17 successively stops the suction processing withrespect to the vacuum chambers corresponding to the stuck second filmsubstrate 20B. Switching of the suction processing with respect to thevacuum chambers is serially performed until the attracting and holdingunit 12 moves from the sticking start position P1 to a sticking endposition P2 (as indicated by an arrow in FIG. 2) after the stickingstart time.

Referring to FIG. 2 illustrating a state in which the attracting andholding unit 12 moves to a substantially central position of the curvedattracting surface 15, a description is now made of the specificoperations of the above processing.

In the state illustrated in FIG. 2, when the attracting and holding unit12 rotates in the direction as indicated by the arrow A while the mold11A relatively moves to the direction as indicated by the arrow V, thefirst vacuum chamber 13-1 is caused to oppose the film substrate 20B.Thus, the suctioning unit 17 starts applying the suction processing tothe first vacuum chamber 13-1. Accordingly, when the film substrate 20Bcontacts the first attracting surface 14-1, the film substrate 20B isheld by the first attracting surface 14-1.

Conversely, in the state illustrated in FIG. 2, when the attracting andholding unit 12 rotates in the direction as indicated by the arrow Awhile the mold 11A relatively moves to the direction as indicated by thearrow V, the film substrate 20B held by the sixth attracting surface14-6 is stuck to the film substrate 20A. However, if the suctionprocessing with respect to the sixth vacuuming chamber 13-6 continuesafter the film substrate 20B is stuck to the film substrate 20A, theretaining force (suctioning force) of the film substrate 20B at thesixth attracting surface 14-6 acts in turn as a force for separating thefilm substrate 20B from the film substrate 20A.

In view of this problem, the suctioning unit 17 is configured to stopthe suction processing with respect to the sixth vacuum chamber 13-6corresponding to the sticking end position after the film substrate 20Bis stuck to the film substrate 20A. By the implementation of the aboveprocessing along with the movement of the attracting and holding unit 12on the curved attracting surface 15A and the rotation of the attractingand holding unit 12 about the drum rotary shaft 40, the film substrate20B can be reliably held over a prescribed range (over a range of 180°as indicated by θ in FIG. 2) where the film substrate 20B opposes theattracting and holding unit 12. Further, since the holding of the filmsubstrate 20B is immediately released after the film substrate 20B isstuck to the film substrate 20A, the separation of the film substrate20B from the film substrate 20A caused by the attracting and holdingunit 12 can be surely prevented.

As described above, the film sticking device 10A illustrated in FIG. 2is configured to stick and shape the film substrates 20A and 20B bymoving the cylindrical attracting and holding unit 12 on the curvedattracting surface 15A having a desired shape provided on the mold 11A.Therefore, unlike a conventional technique, the only one mold (the mold11A) is required. That is, since the number of molds leading to highmanufacturing costs can be reduced, the cost reduction of the filmsticking device 10A is attainable. Further, since the two molds are notessential as in the case described above and high-accuracy moldingprocessing is not required to engage the two molds with each other, thecost reduction is also attainable.

Further, the above example describes a case where the two filmsubstrates 20A and 20B are stuck together. However, even in a case wherethree or more film substrates are stuck together, the stick processingcan be performed without replacing the mold 11A. That is, if the numberof film substrates to be laminated is increased, a curvature radius isvaried in accordance with an increase in the thickness of the filmsubstrates. Where the curvature radius of the film substrates is variedby the lamination of the film substrates as described above, theconventional method, in which the two molds 5A and 5B (see FIGS. 1A and1B) are engaged to shape the substrates, requires plural molds inaccordance with variations in the curvature radius.

Conversely, in the film sticking device 10A described above, the filmsubstrates are laminated with each other on the curved attractingsurface 15A. Therefore, even if the curvature radius of the filmsubstrates is varied, another film substrate is laminated on the upperpart of the film substrates and the suctioning and holding unit 12moving on the upper part performs the stick processing and the shapeprocessing. Consequently, there is no need to change the mold in thefilm sticking device 10A.

Further, the film sticking device 10A is configured such that theattracting and holding unit 12 moves on the curved attracting surface15A from the sticking start position P1 to the sticking end position P2.Therefore, even if air bubbles exist in an adhesive (not shown) used forbonding the film substrates 20A and 20B to each other, the air bubblesare forced to move to the sticking end position P2 along with themovement of the attracting and holding unit 12 and then released fromthe end of the attracting and holding unit 12 to an outside.Accordingly, since there is no need to separately perform air-bubblerelease processing after the film substrates 20A and 20B are stucktogether, the simplification of the stick processing is attainable.Moreover, for the same reason, the occurrence of unevenness in anadhesive can be prevented.

Note that if, for example, substrates having liquid crystal for anelectronic paper formed therein are used as the film substrates 20A and20B, these substrates have higher rigidity than general-purpose resinfilms and are thus hard to be bent. Therefore, if the electronic paperis applied to the mold 11A having the projecting curved attractingsurface 15A illustrated in FIG. 2, variations would occur in the initialcurved shape of the electronic papers, which may interfere with anappropriate display.

In this case, it is effective to use a mold 11B having a recessed curvedattracting surface 15B as illustrated in FIG. 4. Further, if a liquidcrystal implanting step is performed after all film substrates arelaminated with each other, physical influences on liquid crystal due tothe lamination of the film substrates can be prevented.

Next, a description is made of a film sticking device according to anembodiment of the present invention based on the basic principledescribed above.

FIGS. 5 through 9 are diagrams for illustrating the film sticking device30 according to the embodiment of the present invention. FIG. 5 is aconfiguration diagram of the film sticking device 30. FIGS. 6A and 6Bare diagrams for illustrating an attracting drum 12 (the attracting andholding unit 12) provided in the film sticking device 30. FIG. 7 is ablock diagram illustrating the control system of the attracting drum 12of the film sticking device 30. FIG. 8 is a timing chart illustratingthe timing of ON/OFF in suction processing with respect to the vacuumchambers of the attracting drum 12. FIG. 9 is a flowchart illustratingthe operations of the film sticking device 30. Note that in FIGS. 5through 9, components equivalent to those shown in FIGS. 2 and 3 aredenoted by the same reference numerals and their descriptions areomitted here.

First, referring to FIG. 5, a description is made of the entireconfiguration of the film sticking device 30. The film sticking device30 according to this embodiment is a device that sticks together resinfilm substrates (hereinafter referred to as film substrates 20A and 20B)used for an electronic paper.

The film sticking device 30 is composed of the mold 11A, the attractingdrum 12 acting as the attracting and holding unit, the suctioning unit17, a feeding reel 31, a spacer dispersing unit 32, an adhesive curingunit 34, a dispenser 35, a feeding stage 37, a film cutter 39, and thelike.

The mold 11A has the curved attracting surface 15A (specifically, theprojecting semi-cylindrical surface) on its side opposing the attractingdrum 12. In this embodiment, the curved attracting surface 15 projectsupwardly. The curved attracting surface 15A has a multiplicity of minuteholes formed therein. As the suctioning unit 17 is driven, suctionprocessing is applied through the minute holes of the curved attractingsurface 15A. The film substrate 20A is held on the curved attractingsurface 15A by the suction processing.

The feeding stage 37 is provided at the lower part of the mold 11A. Thefeeding stage 37 has the function of moving the mold 11A in a horizontaldirection in FIG. 5. Although the attracting drum 12 described below isfixed, the attracting drum 12 is configured to be capable of relativelymoving in the horizontal direction in FIG. 5 along with the movement ofthe mold 11A by the feeding stage 37.

The attracting drum 12 has a cylindrical shape and is configured torotate about the drum rotary shaft 40 in a direction as indicated by anarrow A in FIG. 5. The attracting drum 12 has the function of sticking(attaching) the film substrate 20B to the film substrate 20A byrelatively moving on the mold 11A.

The attracting drum 12 has plural (eight in this embodiment) internalvacuum chambers of the first vacuum chamber 13-1 through the eighthvacuum chamber 13-8. The peripheral surfaces of the first vacuum chamber13-1 through the eighth vacuum chamber 13-8 are, respectively, the firstattracting surface 14-1 through the eighth attracting surface 14-8having a multiplicity of minute holes formed therein.

As illustrated in FIG. 6A, the first vacuum chamber 13-1 through theeighth vacuum chamber 13-8 are, respectively, connected to first ends ofcommunicating pipes 42. Further, the other ends of the communicatingpipes 42 are, respectively, connected to the suctioning unit 17. Asillustrated in FIG. 6B, the communicating pipes 42 are provided insidethe drum rotary shaft 40. Accordingly, even if the suction drum 12rotates, it is possible to apply the suction processing to the firstvacuum chamber 13-1 through the eighth vacuum chamber 13-8.

Further, a first switching valve 47-1 through an eighth switching valve47-8 are, respectively, provided in the midways of the communicatingpipes 42 through which the suctioning unit 17 communicates with thefirst vacuum chamber 13-1 through the eighth vacuum chamber 3-8 (seeFIG. 7). Accordingly, by the switching of the first switching valve 47-1through the eighth switching valve 47-8, it is possible to separatelyapply the suction processing to the first vacuum chamber 13-1 throughthe eighth vacuum chamber 13-8.

When the suctioning unit 17 is driven and the valves 47-1 through 47-8are opened to apply the suction processing through the minute holes ofthe first attracting surface 14-1 through the eighth attracting surface14-8 of the first vacuum chamber 13-1 through the eighth vacuum chamber13-8, the film substrate 20B is attracted onto the curved attractingsurface 15A. Thus, the film substrate 20B is held by the mold 11A.

At this time, by the appropriate adjustment of the opening and closingof the valves 47-1 through 47-8, the suctioning unit 17 is allowed toseparately apply the suction processing to the first vacuum chamber 13-1through the eighth vacuum chamber 13-8. Thus, the attracting drum 12 canhold the film substrate 20B over its prescribed angle range rather thanat its entire circumference.

The attracting and holding unit 12 thus configured is capable ofapplying pressure to the mold 11A through a drum pressure-applying unit41 (applied pressure is indicated by an arrow F in FIG. 5). Further, theattracting and holding unit 12 has an angle detecting unit 45 and apressure detecting unit 46 (see FIG. 7). The angle detecting unit 45 isan angle sensor that detects the rotational angle of the attracting andholding unit 12. Further, the pressure detecting unit 46 is a pressuresensor that detects pressure applied by the attracting and holding unit12 through the drum pressure-applying unit 41. As described below, angleinformation detected by the angle detecting unit 45 and applied-pressureinformation detected by the pressure detecting unit 46 are transmittedto a control unit 49.

The feeding reel 31 has the film substrate 20 wound thereon. In thisembodiment, the feeding reel 31 is configured to be capable ofcontinuously feeding the film substrate 20B. The film substrate 20B fedfrom the feeding reel 31 is guided by a guide roller 38 and then woundon the attracting and holding unit 12. After that, the film substrate20B is stuck to the film substrate 20A when the attracting and holdingunit 12 relatively moves with respect to the mold 11A.

This embodiment illustrates a case where the film substrate 20B iscontinuously fed from the feeding reel 31, but it may be so arrangedthat the film substrate 20B is cut in advance so as to have a lengthcorresponding to the length of the film substrate 20A (the length of thecurved attracting surface 15A) and fed to the film sticking device 30.

The spacer dispersing unit 32 is a unit that disperses spacer onto thefilm substrate 20B. As described above, this embodiment refers to thedevice that sticks together the film substrates 20A and 20B used for anelectronic paper. As electronic paper, liquid crystal is implantedbetween the film substrate 20A and the film substrate 20B. Therefore,space for implanting liquid crystal is required between the filmsubstrate 20A and the film substrate 20B. For this reason, the spacerdispersing unit 32 disperses the spacer 33 to form the space.

The dispenser 35 has the function of applying an adhesive 36 forsticking the film substrate 20A and the film substrate 20B together. Inthis embodiment, the dispenser 35 is arranged ahead of the attractingand holding unit 12 relative to the relative movement direction of theattracting and holding unit 12 with respect to the mold 11A.

Thus, the adhesive 36 can be applied to the film substrate 20A beforebeing stuck. After that, the film substrate 20B is pressed against thefilm substrate 20A by the attracting and holding unit 12, whereby thefilm substrate 20A and the film substrate 20B are stuck together. Inthis embodiment, the adhesive 36 is configured to be applied to the filmsubstrate 20A immediately before the film substrate 20A and the filmsubstrate 20B are stuck together, but it may be applied in advance tothe entirety of the sticking surface of the film substrate 20A beforethe film substrate 20A and the film substrate 20B are stuck together. Asdescribed above, the adhesive 36 is applicable in various ways but maybe appropriately selected in consideration of the properties or the likeof the adhesive.

The adhesive curing unit 34 has the function of curing the adhesive 36after the film substrate 20A and the film substrate 20B are stucktogether by the adhesive 36. In this embodiment, the adhesive curingunit 34 is arranged behind the attracting and holding unit 12 relativeto the relative movement direction of the attracting and holding unit 12with respect to the mold 11A.

Curing processing by the adhesive curing unit 34 is selected accordingto the type of the adhesive 36. For example, if the adhesive 36 hasultraviolet curing properties, an ultraviolet irradiating unit is usedas the adhesive curing unit 34. Further, if the adhesive 36 has heatcuring properties, a heating unit is used as the adhesive curing unit34.

In this embodiment, the adhesive curing unit 34 is arranged near theattracting drum 12, and the curing processing is started at a part wherethe film substrate 20A and the film substrate 20B are first stucktogether. However, it is also possible that the entire surfaces of thefilm substrate 20A and the film substrate 20B are stuck together andthen the entire bonding position of the film substrate 20A and the filmsubstrate 20B is cured at once. These curing methods can beapproximately selected in consideration of the properties or the like ofthe adhesive.

The film cutter 39 has the function of cutting the film substrate 20Bwhen the film substrate 20B is fed from the sticking start position P1to the sticking end position P2 by the movement of the attracting andholding unit 12 and stuck to the film substrate 20A. Note that the filmsubstrate 20B may be cut at a position where the film substrate 20B isjust fed from the feeding reel 31. However, in order to maintain a statein which another film substrate to be stuck is attracted onto theattracting and holding unit 12, the film substrate 20B is preferably cutwhen the attracting and holding unit 12 moves to a position as indicatedby dotted lines in FIG. 5 (in a state in which the film substrate 20B isfed beyond the sticking end position P2) from the viewpoint of making atransition to the next sticking operation smooth.

Next, referring to FIG. 7, a description is made of the control systemof the attracting drum 12.

The suctioning unit 17, the drum pressure-applying unit 41, the angledetecting unit 45, the pressure detecting unit 46, and the firstswitching valve 47-1 through the eighth switching valve 47-8 describedabove are connected to the control unit 49. The control unit 49 has thefunction of collectively controlling the operations of the film stickingdevice 30.

The angle information detected by the angle detecting unit 45 and theapplied-pressure information detected by the pressure detecting unit 46are transmitted to the control unit 49. The control unit 49 performs theswitching processing for the first switching valve 47-1 through theeighth switching valve 47-8 based on the angle information.

As described above, the attracting drum 12 is pressed against the mold11A (the curved attracting surface 15A) by the drum pressure-applyingunit 41. If the pressure applied by the drum pressure-applying unit 41is varied in accordance with the movement of the attracting drum 12,even and secured sticking of the film substrate 20A and the filmsubstrate 20B cannot be achieved. Therefore, the control unit 49controls, based on the pressure applied to the mold 11A by theattracting drum 12, the drum pressure-applying unit 41 such that theattracting drum 12 applies constant and secured pressure to the mold11A.

Next, a more specific description is made of the switching control ofthe first switching valve 47-1 through the eighth switching valve 47-8by the control unit 49.

The control unit 49 in this embodiment makes control such that thetiming of opening and closing the first switching valve 47-1 through theeighth switching valve 47-8 is sequentially delayed by 45° as therotational angle of the attracting drum 12. Further, after opening theswitching valves 47-1 through 47-8, the control unit 49 maintains theiropening conditions until the attracting drum 12 rotates by 180°. Then,the control unit 49 performs valve closing processing and performscontrol to maintain the closing conditions of the switching valves 47-1through 47-8 until the attracting drum 12 rotates by 180°. In otherwords, the control unit 49 is configured to make the ON/OFF control ofeach of the switching valves 47-1 through 47-8 through an interval of180°.

FIG. 8 is the timing chart illustrating the ON/OFF of vacuum processingwith respect to the first vacuum chamber 13-1 through the eighth vacuumchamber 13-8 when the control unit 49 performs the above control. Inthis embodiment, a position immediately before the first vacuum chamber13-1 of the attracting and holding unit 12 contacts the film substrate20B is defined as 0°.

When the control unit 49 determines that the attracting and holding unit12 has a rotational angle of 0° according to the angle information fromthe angle detecting unit 45, the control unit 49 opens the firstswitching valve 47-1. Thus, the connection of the first vacuum chamber13-1 to the suctioning unit 17 through the communicating pipe 42 isestablished, and the vacuum processing with respect to the first vacuumchamber 13-1 is started (ON).

Then, when the attracting and holding unit 12 rotates by 45°, thecontrol unit 49 opens the second switching valve 47-2 with the firstswitching valve 47-1 opened. Subsequently, the control unit 49sequentially switches the switching valves 47-3 through 47-8 every timethe attracting and holding unit 12 rotates by 45°. Thus, as illustratedin FIG. 8, the vacuum processing is sequentially applied to the secondvacuum chamber 13-2 through the eighth vacuum chamber 13-8. On the otherhand, the control unit 49 sequentially performs the valve closingprocessing when the switching valves 47-1 through 47-8 remain openeduntil the attracting drum 12 rotates by 180°. FIG. 8 illustrates theswitching timings of the switching valves 47-1 through 47-8 when theattracting drum 12 rotates over a range of 0° through 360°.

As described above, in this embodiment, the position at which the firstvacuum chamber 13-1 (the first attracting surface 14-1) of theattracting and holding unit 12 contacts the film substrate 20B isdefined as 0°. Accordingly, when the first attracting surface 14-1contacts the film substrate 20B, the suction processing is applied tothe first vacuum chamber 13-1. Consequently, the film substrate 20B isattracted and held by the first vacuum chamber 13-1 (the firstattracting surface 14-1).

Where the film substrate 20B is held by the first attracting surface14-1 as described above, the film substrate 20B is in the state of beingwound around the attracting drum 12 over a range of 180°. Thus, the filmsubstrate 20B is in the state of contacting the sixth attracting surface14-6 through the eighth attracting surface 14-8 as well.

As described above, by controlling the switching valves 47-1 through47-8, the control unit 49 makes control to apply the suction processingto the vacuum chambers (the first vacuum chamber 13-1 and the sixthvacuum chamber 13-6 through the eighth vacuum chamber 13-8 in theexample illustrated in FIG. 5) corresponding to the attracting surfaces(the first attracting surface 14-1 and the sixth attracting surface 14-6through the eighth attracting surface 14-8 in the example illustrated inFIG. 5) that contact the film substrate 20B.

As illustrated in FIG. 8, since the attracting surfaces attracting thefilm substrate 20B are switched every time the attracting drum 12rotates by 45°, the attracting drum 12 holds the film substrate 20B overits range of 180° at all times. Thus, the film sticking device 30 canreliably feed the film substrate 20B from the feeding reel 31 and stickthe fed film substrate 20B to the film substrate 20B attached to thecurved attracting surface 15A.

On the other hand, at the position at which the attracting drum 12applies pressure to the film substrates 20A and 20B, the attracting drum12 comes into contact with the curved attracting surface 15A of the mold11A. At this position, the film substrate 20A and the film substrate 20Bare stuck together. Thus, as described above, if the film substrate 20Bremains held by the attracting drum 12 even after the film substrate 20Aand the film substrate 20B are stuck together, the force for holding thefilm substrate 20B by the attracting drum 12 acts in turn as a force forseparating the film substrate 20B from the film substrate 20A.

Therefore, in a state illustrated in FIG. 5, the control unit 49 stopsthe fifth switching valve 47-5 to complete the suction processing withrespect to the fifth vacuum chamber 13-5 (the fifth attracting surface14-5). Thus, the separation of the stuck film substrates 20A and 20B dueto the attracting drum 12 can be prevented. Note that the control unit49 controls the second switching valve 47-2 through the fourth switchingvalve 47-4 so as not to apply the suction processing to the vacuumchambers (the second vacuum chamber 13-2 through the fourth vacuumchamber 13-4 in the example illustrated in FIG. 5) corresponding to theother attracting surfaces (the second attracting surface 14-2 throughthe fourth attracting surface 14-4 in the example illustrated in FIG. 5)that do not contact the film substrate 20B.

As illustrated in FIG. 8, since the attracting surfaces that do notattract the film substrate 20B are also switched every time theattracting drum 12 rotates by 45°, the suction processing is not appliedto the parts of the attracting drum 12 that do not contact the filmsubstrate 20B. Thus, besides preventing the separation of the stuck filmsubstrates 20A and 20B described above, it is possible to suppress theuseless driving of the suctioning unit 17 and attain the reduction ofrunning costs.

Next, a description is made of the operations of the film stickingdevice 30 thus configured. FIG. 9 is a flowchart illustrating theoperations of the film sticking device 30 at the time of sticking thefilm substrates 20A and 20B together.

When the stick processing is started, processing for attaching the filmsubstrate 20A to the mold 11A is performed in step 10 (step isabbreviated as S in FIG. 9). In this embodiment, the film substrate 20Acut into a predetermined shape is placed on the curved attractingsurface 15A. However, it is also possible to use the same feeding reelas the feeding reel 31 onto which the film substrate 20A is wound andcontinuously feed the film substrate 20A onto the curved attractingsurface 15A.

Further, a positioning mark 44 is provided at the sticking startposition P1 of the curved attracting surface 15A. In attaching the filmsubstrate 20A to the curved attracting surface 15A, the curvedattracting surface 15A and the film substrate 20A are positioned basedon the positioning mark 44. Thus, the film substrate 20A can be attachedto the predetermined position on the curved attracting surface 15A withhigh accuracy.

When the film substrate 20A is attached to the predetermined position onthe curved attracting surface 15A as described above, the control unit49 drives the suctioning unit 17. Thus, the film substrate 20A isattracted onto the curved attracting surface 15A and held by the mold11A.

Next, in step 20, the tip end of the film substrate 20B fed from thefeeding reel 31 is set to the curved attracting surface 15A with thepositioning mark 44. Consequently, the film substrate 20A and the filmsubstrate 20B are positioned and overlapped with each other at thesticking start position P1.

Then, in step 30, the adhesive 36 is applied to the substrate 20A by thedispenser 35. Further, while the attracting drum 12 moves to thesticking start position P1, the control unit 49 drives the drumpressure-applying unit 41 to apply predetermined pressure to the mold11A. Thus, the pressure is also applied to the film substrate 20A andthe film substrate 20B interposed between the attracting drum 12 and themold 11A, whereby the film substrate 20A and the film substrate 20B arestuck together.

In step 40, the feeding stage 37 starts moving in the direction asindicated by the arrow V. Thus, the attracting drum 12 starts relativelymoving on the curved attracting surface 15A in a direction opposite tothe direction as indicated by the arrow V. At this time, the dispenser35 is arranged ahead of the attracting and holding unit 12 relative tothe relative movement direction (the direction opposite to the directionas indicated by the arrow V) of the attracting and holding unit 12 withrespect to the mold 11A. Therefore, the adhesive 36 is sequentiallyapplied to the film substrate 20A. Further, as the attracting drum 12moves, the film substrate 20B is sequentially pressed against the filmsubstrate 20A onto which the adhesive is applied so as to perform thestick processing.

At this time, the attracting drum 12 is configured to move over a rangeof 180° with the film substrate 20B attracted and held thereon asdescribed above, press the film substrate 20B against the film substrate20A so as to be stuck together, and immediately release the holding ofthe film substrate 20B by the attracting drum 12 after the filmsubstrate 20A and the film substrate 20B are stuck together. Thus, theseparation of the film substrate 20B from the film substrate 20A due tothe attracting drum 12 can be surely prevented.

Further, processing in step 40 is performed during a period in which theattracting drum. 12 moves from the sticking start position P1 to thesticking end position P2. Therefore, even if air bubbles exist in theadhesive 36 used for bonding the film substrates 20A and 20B to eachother, the air bubbles are forced to move to the sticking end positionP2 along with the movement of the attracting drum 12 and then releasedfrom the end of the attracting drum 12 to an outside.

Accordingly, no air bubbles remain inside the adhesive 36 after the filmsubstrates 20A and 20B are stuck together and thus there is no need toseparately perform the air-bubbles release processing after the filmsubstrates 20A and 20B are stuck together, which in turn makes itpossible to simplify the stick processing. Moreover, since theattracting drum 12 is caused to apply constant pressure to the mold 11Awhen the control unit 49 controls the drum pressure-applying unit 41,the occurrence of unevenness in the adhesive 36 can also be prevented.

In step 50, the adhesive curing unit 34 performs the curing processingon the adhesive 36. In this embodiment, since ultraviolet curing resinis used as the adhesive 36, the adhesive curing unit 34 irradiates theadhesive 36 with ultraviolet rays. In this case, the adhesive curingunit 34 is arranged behind the attracting and holding unit 12 relativeto the relative movement direction (the direction opposite to thedirection as indicated by the arrow V) of the attracting and holdingunit 12 with respect to the mold 11A. Therefore, the adhesive curingunit 34 sequentially performs the curing processing on the adhesive 36applied by the dispenser 35.

The processing in steps 30 through 50 is performed until the attractingdrum 12 moves to the sticking end position P2. When the film substrates20A and 20B are stuck together over a range from the sticking startposition P1 to the sticking end position P2, the film substrates 20A and20B are cut by the film cutter 39 and thus the stick processing for thefilm substrate 20A and the film substrate 20B is completed.

Since the film sticking device 30 according to the embodiment describedabove is configured to stick and shape the film substrates 20A and 20Bby moving the attracting drum 12, the film sticking device 30 canperform the sticking processing for the film substrates 20A and 20B onlywith the one mold 11A. That is, since the number of molds leading tohigh manufacturing costs can be reduced, the cost reduction of the filmsticking device 30 is attainable. Further, since high-accuracy moldingprocessing is not required to engage plural molds with each other, thecost reduction is also attainable.

Note that in the embodiment described above, the mold 11A has anupwardly projecting semi-cylindrical shape. However, as illustrated inFIG. 10, a curved attracting surface 15C of a mold 11C may be afree-form surface. Further, the film sticking device according to theembodiment is attainable even if the attracting drum and the mold arereversely arranged in a vertical direction.

All examples and conditional language recited herein are intended forpedagogical purposes to aid the reader in understanding the presentinvention and the concepts contributed by the inventor to furthering theart, and are to be construed as being without limitation to suchspecifically recited examples and conditions, and the organization ofsuch examples in the specification does not relate to a showing of thesuperiority or inferiority of the present invention. Although theembodiment of the present invention has been described in detail, itshould be understood that the various changes, substitutions, andalterations could be made hereto without departing from the spirit andscope of the present invention.

1. A film sticking device that sticks a first film substrate and asecond film substrate together on a curved-surface shape, the filmsticking device comprising: a mold having a curved attachment surface towhich the first film substrate is attached, the curved attachmentsurface being formed into a desired curved-surface shape; an attractingand holding unit that is configured to be capable of relatively movingon the curved attachment surface and has plural vacuum chambers on whichan attracting surface for attracting and holding the second filmsubstrate is provided; and a suctioning unit capable of separatelyapplying suction processing to the plural vacuum chambers; wherein thesuctioning unit is configured to start, as the attracting and holdingunit moves, the suction processing of the vacuum chamber correspondingto a position opposing the second film substrate and sequentially stop,as the second film substrate is stuck to the first film substrate, thesuction processing of the vacuum chamber corresponding to the stucksecond film substrate.
 2. The film sticking device according to claim 1,further comprising: a rotational angle detecting unit provided in theattracting and holding unit; wherein the suctioning unit is configuredto switch the suction processing of the vacuum chamber based on arotational angle of the attracting and holding unit detected by therotational angle detecting unit.
 3. The film sticking device accordingto claim 1, further comprising: a pressure applying unit that appliespressure to press the attracting and holding unit against the mold; apressure detecting unit that is provided in the attracting and holdingunit and detects the pressure applied to the mold; and a pressurecontrol unit that controls, based on the pressure detected by thepressure detecting unit, the pressure applying unit so as to press theattracting and holding unit against the mold with constant pressure. 4.The film sticking device according to claim 1, wherein a moving unitprovided in the mold is configured to cause the attracting and holdingunit to move on the curved attachment surface with the attracting andholding unit fixed.
 5. The film sticking device according to claim 1,wherein a communicating pipe communicating between the vacuum chamberand the suctioning unit is arranged inside a central rotary shaft of theattracting and holding unit.
 6. The film sticking device according toclaim 1, wherein at least the second film substrate is configured to becapable of being continuously fed from a feeding reel, and a film cuttercapable of cutting the second film substrate fed from the feeding reelinto a desired length is provided.
 7. The film sticking device accordingto claim 1, wherein the first and second film substrates are arrangedwith a liquid crystal for an electronic paper held therebetween.
 8. Thefilm sticking device according to claim 6, wherein a spacer dispersingunit that disperses a spacer onto the second film substrate is providedbetween the feeding reel and the attracting and holding unit.
 9. A filmsticking method of a film sticking device in which plural filmsubstrates are stuck together on a curved-surface shape, the filmsticking method comprising: attaching a first film substrate to a moldhaving a curved attachment surface formed into a desired curved-surfaceshape; and sticking a second film substrate to the first film substrateby an attracting and holding unit that is configured to be capable ofrelatively moving on the curved attachment surface and has plural vacuumchambers each of which is provided with an attracting surface forattracting and holding the second film substrate; wherein, in thesticking, suction processing of the vacuum chamber corresponding to aposition opposing the second film substrate is started, and the suctionprocessing of the vacuum chamber corresponding to the stuck second filmsubstrate is sequentially stopped as the second film substrate is stuckto the first film substrate along with a movement of the attracting andholding unit.
 10. The film sticking method according to claim 9, whereina rotational angle detecting unit is provided in the attracting andholding unit, and the suction processing of the vacuum chamber isswitched based on a rotational angle of the attracting and holding unitdetected by the rotational angle detecting unit.
 11. The film stickingmethod according to claim 9, wherein the film sticking device isprovided with: a pressure applying unit that applies pressure to pressthe attracting and holding unit against the mold; a pressure detectingunit that is provided in the attracting and holding unit and detects thepressure applied to the mold; and a pressure control unit that controls,based on the pressure detected by the pressure detecting unit, thepressure applying unit so as to press the attracting and holding unitagainst the mold with constant pressure.
 12. The film sticking methodaccording to claim 9, wherein, when the mold moves relative to the fixedattracting and holding unit, the attracting and holding unit relativelymoves on the curved attachment surface.
 13. The film sticking methodaccording to claim 9, wherein at least the second film substrate isconfigured to be capable of being continuously fed from a feeding reel,and the second film substrate is cut by a film cutter after the secondfilm substrate fed from the feeding reel is stuck to the first filmsubstrate.
 14. The film sticking method according to claim 9, whereinthe first and second film substrates are arranged with a liquid crystalfor an electronic paper held therebetween.
 15. The film sticking methodaccording to claim 13, wherein a spacer is dispersed onto the secondfilm substrate during a period in which the second film substrate is fedfrom the feeding reel to the attracting and holding unit.
 16. Anelectronic paper manufacturing method in which first and second filmsubstrates acting as substrates and arranged with a liquid crystal of anelectronic paper held therebetween are stuck together on acurved-surface shape, the electronic paper manufacturing methodcomprising: attaching the first film substrate to a mold having a curvedattachment surface formed into a desired curved-surface shape; andsticking the second film substrate to the first film substrate by anattracting and holding unit that is configured to be capable ofrelatively moving on the curved attachment surface and has plural vacuumchambers each of which is provided with an attracting surface forattracting and holding the second film substrate; wherein, in thesticking, suction processing of the vacuum chamber corresponding to aposition opposing the second film substrate is started, and the suctionprocessing of the vacuum chamber corresponding to the stuck second filmsubstrate is sequentially stopped as the second film substrate is stuckto the first film substrate along with a movement of the attracting andholding unit.